Infra red reflecting yarns and fabrics



Unit

Arthur Noel De Thier, Woodridings, The Firs, Bowdon, Cheshire, EnglandNo Drawing. Filed May 27, 1958, Ser. No. 738,000 11 Claims. 01. 139-426)This invention relates to textile yarns and fabrics, more particularlyto the use of blends of colors to reflect infrared radiation. Thepresent application is a continuationin-part of copending applicationSerial No. 521,419, filed July 11, 1955, entitled Textile Yarns andFabrics, now abandoned.

It is an object of the invention to produce yarns and fabrics having ahigh resistance to penetration bythe heat rays of the sun.

Another object of the invention is to produce fabrics which, whilstpreserving such resistance to penetration, are also of an improvedstructure and appearance as will appear more fully below.

With suitable variation as to weave and weight, and features such ascount of yarn and nature of fibers, and

with either plain or fancy yarns, the improved fabrics of the presentinvention are useful inter alia for the making of clothes for tropicalwear, and for many other similar purposes. It is possible, for example,to produce fabrics of synthetic fibers, having substantially theappearance of wool or worsted fabrics so that, for example, a relativelylightweight heat-resisting dress fabric, suiting or coat fabric can havethe general appearance of being heavier, heat-retaining fabric. Theinvention also' allows of fabrics being produced which are useful asheat-resisting tent cloth or awning material, especially fortropicalclimates.

According to this invention, a yarn is made up from a mixture of fiberswhich respectively are of the primary colors of the solar spectrum, eachcolor being obtained by the use of dyestuffs known to offer some degreeof reflectance to infra-red rays, namely red, yellow and blue; or red,green and blue, and so that such fibers are present in the respectivecolors throughout the whole of the yarn in such proportions as to givea'reflectance approximating to that of white when tested by infra-redphotography.

These proportions cannot be stated precisely as applying to all cases,since man-made colors cannot equal the purity and regularity of thecolors in the solar spectrum and, moreover, it is impossible for colormakers to guarantee identity of shade and infra-red reflectance at alltimes.

A fabric made from a yarn of this kind has a degree of heat resistancesubstantially equal to that of white when subjected to direct radiantheat and it may also be given a very pleasing appearance. In some casesa tweed-like efiect is obtainable in a fabric produced from spun manmadefibers. Other novel and attractive effects are obtainable according tothe structure of the yarn and the fabric.

The improved yarns may be produced in various ways.

They may for examp'e be made from dyed natural fibers quired threecolors and then squirted or extrudc: in the usual way, the resultingfilaments are cut to staple length tates fiatent '0 ice and the threebatches of cut fibers are then thoroughly mixed together in the requiredproportions. The mixture is then spun" into yarn. If desired, naturalfibers ofthe same color as one or more of the batches of syntheticfibers may be introduced into the mixture before spinning, so long asthe combined colors in the total mixture are such as to give therequired high-reflectance toinfra-red rays.

In another mode of operation, batches of loose fibers or cut filamentsof staple length are dyed in the respective colors, and mixed in therequired proportions before being spun into yarn. I

The aim in both these cases is to have in the finished fabric, atallparts of the fabric, closely associated fibers of the several primarycolors in the proportions giving a reflectance to infra-redapproximating closely to that of white. The dyes used must be such aswill themselves reflect infra-red rays. Preferably, the fibers dyedtherewith are deep dyed.

Any known type of weave may be adopted, according t the effect desiredand the fabric may be finished (other than by dyeing) in any waynecessary for particular uses of it. The invention is equally applicableto the making of fabrics from mixtures of materials (elg. cotton andman-made fibers, or wool and man-made fibers) as to the making offabrics of uniform materials, whether of vegetable, animal, artificialor synthetic origin. Felted fabrics may also be produced according tothis invention.

In a particular example of the improved fabric, by way of illustration,the fabric is a 54 x44 cloth, woven on a 2 x 2 box loom from spunviscose yarns of 12s cotton count both in the warp and weft which yarnshave been made up from a mixture of cut fibers obtained from threedope-dyed batches of viscose. The proportions of color areapproximately:

Percent Red 25 Gre a 25 Blue S0 The proportions of the three primarycolors forming white light in the solar spectrum, ascertained as aresult of tests carried out at the Manchester (England) College ofScience and Technology are:

X, Y and Z are the points of a trianglewithin which any particular coloris plotted. The chart containing this diagram is that produced by theCommission Internationale de lEclairage in 1931, being the acceptedstandard of color definition used in photometry. The trichromaticcoordinates gives the position of the color within the triangle.

The relative proportions of the dyed yarns used is dependent upon thedepth of colors available and their degree of resistance to thepenetration of the infra-red rays, as will readily be appreciated by theskilled artizan.

Before spinning into yarn, the viscose or other dyed fibers may havewhite fibers added to the mixture, when light pastel shades arerequired.

In order to provide fabrics in a range of colors required by thetrade-the preparation of thefibers for'spi'nningimay be varied withoutsacrifice of the heat-resisting qualities,

Patented mam 2G,: ffiii Thus, grey, grey-green, grey-blue, brown and arange of 'mixture shades can be produced by mixing appropriate amountsof the three primary colors together. The absorption will fall to zerobeyond the absorption bands, whereas in a mixture of black and white orin a solid brown, khaki or tan there will still be strong absorption inthe infra-red.

The following table gives various examples of mixtures of said primarycolors which, when made into textile materials, produce the desiredresults of the invention.

Blue Green Yellow Red Percent Percent Percent Percent In practice, greyand other colored fabrics made under the three-color specification arealmost as good as white,

.while similar shades of grey obtained by black-white mixing, show heatabsorption which is more than 50% greater,

, being almost as bad as black.

green, thecquivalent of blue and yellow may be used.

What is claimed is: l. A textile fabric wherein said fabric is wovenfrom spun yarns consisting of a blend of the primary colors of the solarspectrum and which is essentially of the colors red, blue, and at leastone color taken from the class consisting of yellow and green, in suchproportions as to give a reflectance of infra-red rays approximatingthat of white.

2. A textile fabric wherein said fabric is woven from spun yarnsconsisting of a blend of the primary colors of the solar spectrum andwhich is essentially of the colors red, blue, and at least one colortaken from the class consisting of yellow and green, in such proportionsas to give a reflectance of infra-red rays approximating that of white,

' said fabric being multi-colored. a 3. A textile fabric wherein saidfabric is woven from" spun yarns consisting of a blend of the primarycolors of the solar spectrum and which is essentially of the colors red,blue, and at least one color taken from the class consisting of yellowand green, in such proportions as to give a reflectance of infra-redrays approximating that of white,

' the proportions of said blended colors being approximately 4 A textilefabric wherein said material is woven from I spunyarns consisting of ablend of the following primary colors of the solar spectrum inapproximately the stated proportions:

Percent Blue 40 Gr e 30 Red 30 and having a reflectance to infra-redrays approximating that of white.

5. A textile fabric wherein said material is woven from spun yarnsconsisting of a blend of the foliowmg primary colors of the solarspectrum in approximately the stated proportions:

Percent Blue 30 Green 40 Red 30 and have a reflectance to infra-red raysapproximating that of white.

6. A textile fabric wherein said material is woven from spun yarnsconsisting of a blend of the following primary colors of the solarspectrum in approximately the stated proportions:

Percent Blue 50 Green 25 Re 25 and having a reflectance to infra-redrays approximating that of white.

7. A textile fabric wherein said material is woven from spun yarnsconsisting of a blend of the following primary colors of the solarspectrum in approximately the stated proportions:

Percent Blue 42 Green 14 Red 24 Percent Rlue 35 Yellow 35 Red 30 andhaving a reflectance to infra-red rays approximating that of white.

9. The method of making a textile yarn wherein the yarn is made up fromfibers which respectively are of the primary colors of the solarspectrum, each color being obtained by the use of dyestuffs known tooffer some degree of reflectance to infra-red rays (i.e. red, blue and acolor taken from the class consisting of yellow and green) and so thatthroughout the whole of the yarn fibers of the respective colors arepresent in proportions such as to give a reflectance approximating tothat of white when tested by infra-red photography.

10. A textile material having filaments of red, green and blue in suchproportions as to totally reflect substantially all of the infra-redrays of the solar spectrum.

11. A textile material having filaments of red, green and blue in suchproportions as to totally reflect substantially all of the infra-redrays of the solar spectrum, said red being the smallest constituent andsaid blue being the largest constituent.

References Cited in the file of this patent UNITED STATES PATENTS2,462,842 Burgess Mar. 1,1949 2,542,314 De Lacotte Feb. 20, 19512,671,250 Fidell Mar. 9, 1954 2,863,788 Vartanian et al Dec. 9, 1958OTHER REFERENCES

